My baby boy left kidney/heart concerns

So I went to the hospital today at fetal medicine to get an ultrasound done to check to see if baby head is measuring right.. come to find out that his head was perfectly fine but dr comes back saying she concerned about the left kidney that she doesn’t see and that he might not have one.. Then she says his heart might not be normal which I think is bs cause he is a very active baby and my OB dr said everything looked good to her.. so now that I got that news that I didn’t want to hear I’m worried and freaking out now😏 she wants me to see a fetal echo specialist to check on my baby heart to make sure everything ok.. has anyone else gone through this?? Cause I’m scared and worried now😔😢💔